At the end of the Glob Patterns and Wildcards lesson, you read that you were going to learn about the groups, users, permissions, and the superuser. In this lesson, you’ll dive into those topics.

As you manipulate certain files or directories, you might find out that you don't have permission to edit a file, or even access it. This helpful security measure can sometimes be frustrating, but you can get around it and make edits to a protected file. This lesson will teach you in a hands-on way!

In this lesson, we’ll cover users and permissions in the terminal from top to bottom: why users are important in Unix based systems, what permissions are, how to modify permissions, and how to handle file ownership. In addition, you will learn how to modify permissions in two ways: Symbolic Notation, and Octal Notation. You'll also discover the command you can execute to check existing files for a specific file.

Finally, you'll learn about the superuser. Superusers can do everything on a Unix based system and can override anything or make any changes to anything. With great power comes great responsibility, and the superuser is no exception! One wrong move using the sudo (superuser do) command could possibly render your computer useless, so in this lesson you’ll learn to wield this command safely in our browser-based terminal environment (don’t worry, you won’t break our site)!

Getting the hang of Users and Permissions is tough, and the concepts are tough! With every concept learned, we give you an opportunity to practice that concept, and our built-in answer checking system gives you the confidence that you've completely mastered each concept before moving on to the next.

What You'll Learn

  • Why the concept of users are important
  • What groups are for
  • What permissions are and why we care about them
  • How to modify permissions
  • The superuser
  • File ownership

Lesson Outline

1. Users
2. Groups
3. Revisiting ls
4. Permissions
5. Changing Permissions: Symbolic Notation
6. The File Status Command
7. Changing Permissions: Octal Notation
8. The Superuser
9. Changing Ownership
10. Next Steps
11. Takeaways